Good starting point for WMI programming?

[Tripredacus]

I am working on a project that I want to be able to read and use info from the WMI. I have gotten some info from TechNet and MSDN but it seems to make my head spin. I am also not sure what interface I will use to write the code. It will either be VBScript (with an HTA) or AutoIT or Flash Projector.

So can anyone post me some good WMI guides and tutorials and code examples and such?

[uid0]

For vbs code examples, try scriptomatic (info).

[Glenn9999]

WMI Code Creator might be interesting, too.

But seriously, I know what you're dealing with. I'm still trying (off and on) to write a good WMI interface for what I'm working on. Hopefully I can get it figured out soon.

[gunsmokingman]

This Link is to all the Win32 Classes for Wmi.

[jaclaz]

Also:

http://activexperts.com/admin/wmi/

http://www.activexperts.com/activmonitor/w...t/adminscripts/

http://technet.microsoft.com/en-us/library/ee156560.aspx

http://www.robvanderwoude.com/wmistart.php

http://www.robvanderwoude.com/wmigen.php

http://www.robvanderwoude.com/wmiexamples.php

jaclaz

[cluberti]

I'd have to say the WMICodeCreator and the MSDN class articles are probably the best way to go. Regardless of vbscript or autoit (although PowerShell is out there too), learning WMI via vbscript+WMICC+MSDN is probably the most straightforward way. WMI is pretty easy if you already know the framework around it (vbscript, AutoIT, PS, .NET, etc) - it's just a structured query language, basically.

[Glenn9999]

This Link is to all the Win32 Classes for Wmi.

Thanks for the link, I just got my WMI interface done (I think, except for a few error related checks), and need some stuff to test it on

[tain]

I'm no programmer like these studs but I've learned a bit about WMI by using Samurize and editing config files. It has a WMI interface that I like to tinker with. Nothing serious, but why can't you have some fun while you're at it?

Doing this in conjunction with AHK.

[gunsmokingman]

Here is a little code that will show you how to convert the WMI OS Install Date and OS Last Boot Date, to a more readable format.

 Dim Tme :Set Tme = CreateObject("WbemScripting.SWbemDateTime")
 Dim Wmi :Set Wmi = GetObject("winmgmts:{impersonationLevel=impersonate}!\\.\root\CIMV2")

 Dim Obj
 Dim BDate, IDate
	For Each Obj In Wmi.ExecQuery("SELECT * FROM Win32_OperatingSystem")
	 Tme.Value = Obj.LastBootUpTime
	 BDate = Left(MonthName(Tme.Month),3) & ", " & Left(WeekdayName(Weekday(Tme.GetVarDate)),3) & vbTab & Tme.GetVarDate
	 Tme.Value = Obj.InstallDate
	 IDate = Left(MonthName(Tme.Month),3) & ", " & Left(WeekdayName(Weekday(Tme.GetVarDate)),3) & vbTab & Tme.GetVarDate
	Next
  MsgBox _
  "Installed Date" & vbTab & IDate & vbCrLf & _
  "Last Boot Date" & vbTab & BDate,4128,"Wmi Time Demo"

[Glenn9999]

Okay I got something reasonably working now from some examples, except for a few points:

1) I'm not a complete expert on COM by any means, but I'm finding it hard to procedurize things, because I'm getting an access violation. I find this happens when I try to make all my statements I use to connect to WMI into a function (eg. ConnectWMI(bla, bla, bla); ). Any ideas? This seems to be related to my attempts to clean things up. Remove that, and no crashes. Still need to clean things up to prevent memory leaks, though, so any ideas on this one would be good.

2) Error checking? I looked over the WbemObjectSet object and I'm not seeing anything jump out at me (nothing new, most of this stuff isn't documented too well - I'm fighting the WMP player object on that for another project) in that category. Usually when I enter a statement with an error in it, it just hangs there for a while and then comes back to prompt, but it would be nice to be able to come back with "Incorrect Table Name", or some such thing. I realize I could check the count if it's = 0 (and I do that), but I'm wondering if anything nicer could be done easily enough.

3) Then one thing I'm not sure of is this... I'm guessing from what I've read that there are such things as WMI methods as well? I'm not seeing anything particularly interesting jump out to play with (maybe something in Win32_BaseService?). Any ideas on this one? Edit: It's looking like Win32_Process.Create run against NOTEPAD.EXE ought to do it for this one...should be fine here

I will say once you get the interface returning data, the WMI part is a breeze if you have the documentation and know SQL.

Edited February 16, 2010 by Glenn9999

[cluberti]

1) I'm not a complete expert on COM by any means, but I'm finding it hard to procedurize things, because I'm getting an access violation. I find this happens when I try to make all my statements I use to connect to WMI into a function (eg. ConnectWMI(bla, bla, bla); ). Any ideas? This seems to be related to my attempts to clean things up. Remove that, and no crashes. Still need to clean things up to prevent memory leaks, though, so any ideas on this one would be good.

Sample?

2) Error checking? I looked over the WbemObjectSet object and I'm not seeing anything jump out at me (nothing new, most of this stuff isn't documented too well - I'm fighting the WMP player object on that for another project) in that category. Usually when I enter a statement with an error in it, it just hangs there for a while and then comes back to prompt, but it would be nice to be able to come back with "Incorrect Table Name", or some such thing. I realize I could check the count if it's = 0 (and I do that), but I'm wondering if anything nicer could be done easily enough.

What language?

[Glenn9999]

Sample?

What language?

Trying this with Delphi. Like was said, write the interface and the rest should take care of itself. But the interface is what needs taken care of. I figured out that using the COM related unit does all the COm initializations/uninitializations so I dropped that. Sample of the relevant code for #1:

WbemLocator := nil;
HRes := CoCreateInstance(Class_SWbemLocator, nil, CLSCTX_INPROC_SERVER,
             ISWbemLocator, WbemLocator);
if HRes <> 0 then
  ShowMessage('Locator instance not created.');
WBEmServices := nil;
WBEmServices := WBEMLocator.ConnectServer('', '\root\CIMV2', '', '', '', '', 0, nil);
if HRes <> 0 then
  ShowMessage('Server connection not created.');
HRes := CoSetProxyBlanket(WbemServices, RPC_C_AUTHN_WINNT, RPC_C_AUTHZ_NONE,
           nil,
           wbemAuthenticationLevelCall, wbemImpersonationLevelImpersonate,
           nil, EOAC_NONE);

...(then later on when all is done, commenting these out fixes my access violations, but not cleaning this up either )
//  WbemServices._Release;
//  WbemLocator._Release;

For #2, it's much like the script that got posted in the thread. Submit a query and then parse the results:

ObjectSet := nil;
ObjectSet := WBEmServices.ExecQuery(Edit1.Text, 'WQL',
         wbemFlagReturnImmediately,
         nil);

I don't see any error checking on the scripts I see posted on here, so it's hard to tell. I don't see anything in the SWbemObjectSet which indicates any error codes, so I'm not really sure that this one might be a possibility.

(FWIW, I can post the exec for this when I get done if it'll help - one of them is a WQL processor, which I'm sure will help in poking around the WQL tables. It works pretty well except for the issues above)

Edited February 16, 2010 by Glenn9999

[Glenn9999]

Okay, I figured out that I didn't need to necessarily worry about clean-up anyway with the format of what I'm using, so I won't worry about posting the WQL program I have.

Edit: Replaced the old one with a newer version. I don't know if the remote connect part works, but the rest seems to work. If you want to connect to the local machine, all you need to do is hit the "Connect" button with nothing in the machine info fields.

Edited February 20, 2010 by Glenn9999